Orthodontics shares a principle with the classic tug of war game: if you want things to move in the right direction you need a good anchor. Anchors help braces and other appliances apply constant pressure to misaligned teeth in the direction they need to go to correct a malocclusion (poor bite).

Orthodontic treatments work in cooperation with an existing oral mechanism that already moves teeth naturally in response to biting forces or other environmental factors. The key to this mechanism is an elastic tissue known as the periodontal ligament that lies between the tooth and the bone. Besides holding teeth in place through tiny attached fibers, the ligament also allows the teeth to move in tiny increments.

Braces’ wires laced through brackets affixed to the teeth exert pressure on them in the desired direction of movement –the periodontal ligament and other structures do the rest. To maintain that pressure we need to attach them to an “anchor”—in basic malocclusions that’s usually the back molar teeth.

But not all malocclusions are that simple. Some may require moving only certain teeth while not moving their neighbors. Younger patients’ jaws and facial structures still under development may also need to be considered during orthodontic treatment. That’s why orthodontists have other anchorage methods to address these possible complications.

One example of an alternate anchorage is a headgear appliance that actually uses the patient’s skull as the anchor. The headgear consists of a strap running around the back of the head and attached in front to orthodontic brackets (usually on molar teeth). The pressure it exerts can trigger tooth movement, but it can also help influence jaw development if an upper or lower jaw is growing too far forward or back.

Another useful anchorage method is a tiny metal screw called a temporary anchorage device (TAD) that is implanted into the jawbone above the teeth through the gums. Orthodontists then attach elastic bands between implanted TADs and specific braces’ brackets or wires to exert pressure on certain teeth but not others with pinpoint accuracy. After treatment the TADs can be easily removed.

Using these and other appliances allows orthodontists to customize treatment to an individual patient’s particular malocclusion. With the right anchor, even the most complex bite problem can be transformed into a beautiful and healthy smile.